Capacitance of cylindrical shells

I know the capacitance of cylindrical shell formula if both cylinder length is same.If cylinders length differs between which the dielctric is sandwitched what is the formula to calculte the capacitance?

All this formula I know.These will workout when both cylinder lengths are same.My question is when there is change in lendth there will be charges dude to fringe effect.Is there any formula to apply during such condition